Active and standby configurations are often used in telecommunications networks to increase network reliability by reducing the likelihood that failure of one device will disable communications in the network. IP telephony call processing hosts, such as media gateway controllers, have been deployed in redundant pairs. However, these redundant pairs are often located in the same physical frame, making the active and standby host susceptible to simultaneous failure due to a power outage, fire, or other occurrence at the site where the physical frame is located.
As used herein, the term “telephony call processing host” refers to a physical entity in a telephony network, and the term “telephony call processing node” refers to a logical entity in a telephony call processing network. A node may include two or more physical hosts, where the hosts are located in the same or in different geographic locations. When a node consists of two redundant hosts, each host may also be referred to as a half-node.
For simplicity, the present invention will be described in terms of nodes consisting of two hosts. However, the methods and systems described herein may be applied to N hosts, where N may be greater than two.
In conventional telecommunication systems, media gateway controllers were redundantly deployed at single locations, but not at geographically diverse locations. Providing redundancy at geographically diverse locations introduces problems because communicating state information in a manner sufficient to enable reliable switchover is problematic when the hosts are located in remote locations.
Accordingly, there exists a need for improved methods and systems for providing redundant telephony call processing hosts at geographically diverse locations.